package leetcode;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: Lenovo
 * Date: 2022-02-16
 * Time: 11:18
 */
public class Day_03 {
    public static void main(String[] args) {

    }
}
class CQueue {
    private Stack<Integer> stack1;
    private Stack<Integer> stack2;

    public CQueue() {
        stack1=new Stack<>();
        stack2=new Stack<>();
    }

    public void appendTail(int value) {
        stack1.push(value);
    }

    public int deleteHead() {
        if(stack2.isEmpty()){
            while(!stack1.isEmpty()){
                stack2.push(stack1.pop());
            }
        }
        if(stack2.isEmpty()){
            return -1;
        }
        else{
            return stack2.pop();
        }
    }
}

/**
 * Your CQueue object will be instantiated and called as such:
 * CQueue obj = new CQueue();
 * obj.appendTail(value);
 * int param_2 = obj.deleteHead();
 */